Core B will have two primary roles in the Program Project. Core B will be responsible for maintaining and supplying shared cell lines/cDNA constructs, fusion proteins, baculovirus constructs, and antibodies for all investigators involved in the Program Project. Secondly, the Core will perform the Abeta ELISA for quantitating total Abeta, Abeta42 (and other ELISA's as they are developed), in a timely and convenient manner for all investigators involved in the Program Project. Core B is basically intended to serve as a central repository for maintaining and supplying a large number of highly useful reagents that have been generated over the last decade by the Investigators involved in the Program Project. These reagents which include a large variety of stably-transfected mammalian cell lines and corresponding transgene cDNA constructs, several fusion proteins/baculovirus constructs and corresponding cell lines and extensive collection of specific polyclonal and monoclonal antibodies greatly facilitate ongoing collaborations and overall experimental efficiency within the Program Project. Since a major molecular consequence of FAD mutations in the presenilin genes as an increase in the ratio of Abeta42:Abeta40, all four projects and the transgenic core will require an effective and convenient means for obtaining quantitative measurements of Abeta. Therefore, Core B will be available to carry out the Abeta ELISA whenever desired by a Program Investigator. While the expenses for maintain the Core reagents and performing the Abeta ELISA (and other ELISAs, e.g. for presenilins, as they become available) will be incurred by Core B, individual project expenses including those for large scale- workup of cell lines for specific biological experiments or protein purifications will be covered by individual project budgets. Core B activities will be overseen by Dr. Tanzi and Dr. Selkoe while day-to-day operations of the Core will be supervised by Dr. Wilma Wasco.